Simulating longshore shoreline change: Improving performance of one-line models

One-line models are a popular reduced-complexity approach to simulating shoreline change driven by gradients in longshore sediment transport. The rate of sediment transport is typically calculated using an empirical formula based on the direction of incident waves relative to the shoreline, such as the CERC (US Army Corps of Engineers, 1984) or Kamphuis (1991) equations. Examples utilising this approach include well- known standalone models of longshore change like GENESIS (Hanson, 1989), CEM (Ashton et al., 2001), and more recently ShorelineS (Roelvink et al., 2020), as well as hybrid models combining cross-shore and longshore processes such as CoSMoS-COAST (Vitousek et al., 2017), COCOONED (Antolínez et al., 2019), and ShorelineEvol (de Santiago et al., 2021).<p></p>